VeJa - Mutant

Hi everyone,
I’m proud to announce a new VeJa plugin, called the Mutant.

The Mutant is a versatile guitar amp simulator that is not based on any ‘real’ amp. Instead it uses tube simulations from various amplifiers that are used together to create something new.

To really shape the sound, the Mutant offers 3 different gain parameters:
-Pregain which is used to crank the preamp of the amplifier.
-Drive which sits in the middle, and can be enabled to really push the amplifier into heavy distortion, or to just add some extra sparkle at lower gain values.
-Postgain which determines how much drive is introduced in the last power stage of the amplifier.

It also offers five tone knobs: besides the regular bass, mid and treble tonestack there are independent depth and presence controls to further dail in the sound to your taste.

It comes with a small selection of presets, made together with @jesse. We can still expand on this collection so if any of you create some awesome sounds please share them :wink:

Comments and feedback are more than welcome!

Enjoy :slight_smile:


Already installed… let’s hear it! :grinning:


this is absolutly massiv - really like the low end and the controls (5150 style on both)

for everyone who’s wondering how it sounds:


I don’t have my Dwarf anymore so I can’t test it (from the above demo it seems like the sound quality shouldn’t be an issue).

However, I have to say that design-wise Mutant seems EXACTLY like the type of amp MOD platform needs.

The interface is not entirely standard but it’s slick and easy to understand (even if cascading gain stages are not common - though not unheard off - within a single amp, guitar drive pedals make the idea somewhat easy to understand). It looks great, it covers a certain, dedicated tonal range (high gain sounds). I also like how users know exactly what kind of amp this is from the name/design alone, but the amp is not modeling anything specific (which might be a losing battle given that Helix and QC are on the market).

Great stuff. The amp selection in Dwarf is already decent, but some of them aren’t very polished. 2-3 more amps like Mutant (and Onyx) covering the low/mid gain side of the spectrum, would probably be enough to present the guitarist using MOD with would could be considered a comprehensive selection.

This is basically what the topic about amps that I’ve made a long time ago was about.


On my way home from Austria atm so I’m curious…does it HEAVY METAL?:smiley:

The Titan didn’t do it for me so I’m curious what this beastie can do


I’ll played around with it a bit more and checked all the presets: this amp can do everything - from clean to classic to crunch and super heavy. I think this amp covers most of the stuff you were expecting.
It polished, easy to use and sounds good immediately.

Some minor question @Jan : why don’t you tease these kind of things? Don’t get me wrong it is great when something like this pops up out of “nowhere” but there are at least 4 Instagram, forum posts etc. and two videos just before the release.


Hello @Jan Jan,

as soon as you posted this, I thought: How much will this plugin cost?
I think you built a bridge between old well-known but not so versatile amps up to that kind of high gain amps that Matt was expecting to fiddle with.
I’m really impressed what this mutant is capable of.

I don’t know if this gap is filled now because I am good at drums and keys.
I am happy for us all, though.

Greetings and God bless, Marius


Thank you all for the positive feedback :slight_smile:

I would’ve liked too, but I also did not want to delay things because of it. I do VeJa outside of MOD with @Jarnoverheesen and with the summer holidays now, it’s hard to know when we can create some meaningful content. It would however still be nice to do so.

The amp has been in an ‘alpha’ state for a bit, and the polishing happened only last week.

I can tease a bit that there are some more amps in this state, mostly needing QA and graphical design. If there are any people willing to help out on this, send me a DM!


yeah I figured and and as a consumer (and based in the open source world) it’s great to not have things delayed for “promotian”.

but nonetheless I think it a staple of the platform.

I think there are a few people here who are are happy to help out with this kind of stuff - me included.
Maybe there could be a closed off group (like the beta but mor specific) that gets a message in advance to help out. Be it creating promotional graphics or soundbites. I know that handing off stuff to other people is also work but at least you know you have that option.

@jon maybe you could move this discussion that has nothing to do with the plugin to a new/other thread.


Not a bad idea!

Reviewing amps ranging from fingerpicking acoustic all the way to metal or musing over graphic designs are both up my alley.

I can’t wait for fire up my rig tonight and start testing it. The clip above sounded promising already!


Ok small follow up

Found a small time frame to test the Mutant

I started off with @spunktsch but it was pushing the Dwarf to nearly 100% so I threw almost everything out. Tested it on my Blues Deluxe just to get a sound going but will test later on this pc with prerecorded samples and an IR cab.

Made a split setup:
A: The Centaur-Mutant pairing @spunktsch
B: The MetalTone (courtesy of @brummer) in front of the Mutant.
Applied some EQ on both.

my conclusion: both setups had their own specific quality and usability and most of all:

:metal: :metal: YES, IT DOES HEAVY METAL! :metal: :metal:

This amp is such a leap forward for me, I’m excited about this one!
Especially since I dind’t have to do much to get something good goign on, and that’s always a good sign. I will be building a new board like this, A/B testing it while adding my vocal chain to it for channel 2. (being able to save parts of chains would help these kinds of workflows but the MOD teams already know that of course, right @jon? :D)

Next step: a new step in my journal; taking he new power supply and a new board (based around the Mutant) to the rehearsal room to use it for the band rehearsal. only 2 rehearsals to go until a new gig so I need to be ready and better than the first time! :smiley:


This is not so much on @Jan plate, but is something that we have been discussing quite a lot. Right now we are not using the marketing (or lack of it) to hold on releases. The truth is that we are with really few resources for marketing and then this things need to be asynchronous.
What we plan is to dedicate concentrated marketing efforts on different things from the platform. You saw a glance of it recently on the CV plugins with the Guitar Synth releases.
What you are suggesting is exactly where we want to go. Hopefully we will get there.


made a first test board with a sample.
No button assignments or anything, just messing around putting a MetalTone BEHIND the Mutant and applying a Calf limiter (beta)

Noticed that this board hogs processor power; I think a lot goes to the Mutant.


I still love the mutant, especially with a MetalTone behind it.


It seems to be hogging processor power on the Dwarf and I can’t incorporate it in my board together with the other stuff I need without maxing out on the cpu and getting artifacts :confused:

I had to go to a @brummer Frog->into ->MetalTone combo instead which sounds great too.
(which works better for me than the intuitive pedal in front of the amp. That didn’t work too well for me but switching them around worked great!)


Welp, I’ve been having a play, and for my needs this amp is head and shoulders above any other in the store. Like, in a whole different league.

I don’t know how you’ve done it, but you’ve done it.


Hi! I tested quite extensively the Mutant in past weeks and I think it is the best amp in the store so far. Great job @Jan !!!

Unfortunately I think it has a two little bugs in volume management.

Bug 1: When you load the pedalboard, 1.CRUNCH is selected and the the volume is very high. The scene does not use the drive channel. Then if you select a scene with drive channel on, let’s say 4.LEAD, the volume goes at normal level and the initial issue disappears.

Bug 2: When I move from 4.LEAD to 5.CLEAN or 8.CHORUS there’s a nasty volume spike. I’ve already experienced this kind of problem with other amps and I don’t know if it is strictly related to Mutant or to MOD platform in general.

Here’s my under testing pedalboard.

I’d like to know from Duo X users what’s the CPU usage on their side. On Dwarf is around 70-78% with buffer size 256.


Hi @redcloud, thanks for your feedback!

When changing presets here I don’t have any odd behavior regarding volumes, I also tried snapshots and those behave fine too.
I also tried your pedalboard and cant seem reproduce bug 1, regarding bug 2, I can hear a bit of a spike but I don’t think the Mutant is fully to blame here, as there are a lot of plugins being toggled at once. One tip I can give is to start using the Drive volume parameter to adjust for volume when the drive channel is enabled instead of making big changes on the main volume per snapshot.

also regarding cpu usage, on my Dwarf at a 128 buffer size just the Mutant and an audio file player run at 36% with no Drive and 44% with Drive. (just to give a comparison the cabsims run at ± 39%). on the DuoX it runs at 18% with no Drive and 24% with Drive.
Your pedalboard runs at 58% at 128 here btw on a DuoX

Hope this helps a bit!


EDIT: Solved. Was caused by “dead” user presets I was unable to delete from Mutant user preset list. Somehow they were conflicting with snapshot settings.

Thanks, here a little video about bug 1

I perform the following steps:

  • Load the pedalboard
  • The pedalboard has initial snapshot 1. CRUNCH
  • Start the audio player and you see the tinygain becomes red (here Mutant drive is off)
  • Load snapshot 2. RHYTHM, start the audio player and you see the tinygain becomes red again (here also Mutant drive is off)
  • Load snapshot 3. HARD, start the audio player and you see the tinygain now is green (here Mutant drive is on)
  • Then go back to snapshot 1. CRUNCH, start the audio player and you see the tinygain now is green (here Mutant drive is off)

Bug 2 Untitled - VEED

It seems that the spike it’s caused by Mutant. I’ll try to mitigate the volume jump somehow but in other situations I would have pre/gain stages fixed (because it would change also saturation) and prefer to have different output volume. Maybe with a “morph” behavior (like I’ve already talked in other thread) spikes could be avoided.

1 Like

hmm so the first one is really odd to me as I cant reproduce it, and the signal level is always the same for each snapshot. It would be good to know if this happens to more people in different setups :thinking:

regarding the second one, there is actually already some “morphing” happening behind the scenes for each parameter, however there is a trade-off between responsiveness and artifices. It gets tricky as snapshots are supposed to be instant, and (right now at least) a plugin cant know the difference between a parameter or a snapshot change. Also, afaik the order in parameters changed when loading a snapshot is ‘random’ so when a volume knob gets “morphed” and a drive stage gets toggled, the order can influence how things react at certain samples.

ps, the drive volume parameter doesn’t change anything in terms of saturation, its there for exactly this purpose to avoid big changes on the master volumes :slight_smile: